The invention relates to a safety ski binding for the releasable holding of a ski boot, having two base parts which together can be swivelled around a pin with a non-circular cross-section which is perpendicular to the top side of the ski and is fixed to the ski. The base parts are braced against the force of a prestressable spring assembly operating between them and in such a manner that they can be moved apart in the longitudinal direction of the boot. The base parts are braced by the spring assembly against opposite sides of the pin which, because of its non-circular cross-section, moves the base parts apart when they swivel from a normal position into an oblique position. Coupling elements are arranged on the base parts which interact with countercoupling elements fixed to the boot for the holding of the ski boot on the ski in a form-locking manner as well as essentially without play in the normal position of the base parts. The countercoupling elements of which, when the base parts are moved apart, release the ski boot. A holding-down device which is arranged on a base part as a coupling element and can be moved between a locked position and an engageable release position, in the direction of the vertical axis of the ski, during its movement into the release position, moves one base part away from the other base part against the resistance of the spring assembly which seeks to restore the base parts into the normal position and thus the holding-down device into the locked position. From the engaged release position, when the ski boot is placed in the binding the holding down device can be stepped down by a part of the ski boot while disengaging in the direction of the locked position. The holding-down device, in the normal position of the base parts, reaches from above over a countercoupling element. An actuating member is provided which is positively coupled with the holding-down device for its arbitrary operation.
A safety ski binding of this type is known from the French Patent Application 77 26029; compare particularly FIGS. 21 to 23 as well as the pertaining description.
In the case of this known ski binding, the holding-down device arranged on one base part has cams which interact with assigned connecting links on the other base part in such a manner that the two base parts, in the release position of the holding-down device, are held in a position in which they are moved away from one another by means of the cams as well as the connecting links paths. As a result, the spring assembly is prevented from pressing the base parts against the pin fixed to the ski; i.e., the frictional connection between the base parts and the pin which is normally caused by the spring assembly, is undone. In order to now avoid an undesirable play of the base parts relative to the pin, a separate detent piston is arranged on one base part which, by means of a separate spring, is pushed against a facing flattened side of the pin. In this manner, an actuating force can be generated which seeks to bring the base parts into a position in which the longitudinal axis of the base parts extends in parallel to the longitudinal axis of the ski and the base part opposite the piston is pushed against the side of the pin facing away from the piston.
This construction is relatively expensive. A large number of parts which are movable relative to one another cause a higher friction. In addition, the release resistance of the ski binding is not influenced solely by the prestressing of the spring assembly, but also by the tensioning of the additional spring acting upon the detent piston.
It is now an object of the invention to achieve, in the case of a ski binding of the initially mentioned type, a simplified construction as well as an improved handling.
According to the invention, this object is achieved by means of the fact that the holding-down device in its release position holds the one base part, against the force of the spring assembly, away from the pin fixed to the ski on which the holding device supports itself directly or indirectly during the process.
According to the invention, it is therefore provided that the holding-down device can interact directly with parts arranged on it or indirectly, by way of transmission parts, with the pin in order to move the base part carrying the holding-down device away from the pin. In this case, the spring assembly, which is clamped in between the two base parts and seeks to push these base parts against one another has the effect that the one base part carrying the holding-down device, by way of the holding-down device or the parts which are connected with it or interact with it, and the other base part remain pressed directly against the pin. Thus, the base parts remain held at the pin without play. In addition, a torque may possibly be generated which seeks to adjust the base parts into a desired alignment relative to the ski. For this purpose, it is only required that either the holding-down device or the parts connected with it or interacting with it or the other base part is held pressed against a non-circular surface of the pin by means of the spring assembly.
Because of the arrangement according to the invention, there is also the possibility to arrange similar holding-down devices on both base parts which, in their release position, hold the respective base part away from the pin.
According to a particularly preferred embodiment of the invention, it may be provided that a cam arranged at the holding-down device rests against one end of a tappet which is guided in the base part carrying the holding-down device so that it can be shifted radially with respect to the pin, and the other end of which is supported on the circumference of the pin. Thus a constructively simple possibility is provided to arrange the holding-down device at a larger distance from the pin in such a manner that the holding-down device can interact with the heel area of the ski boot - or with an area at the tip of the boot.
In addition, it is expedient for the base parts to form a plate which supports the ski boot perpendicularly, and for the countercoupling elements on the boot side to be designed as a plate part on the boot side. In this case, fixedly arranged vertical projections may be arranged on the base parts and interact with the longitudinal edges of the boot-side plate part and thus, in a form-locking manner, fix the boot in the transverse direction of the boot. In order to secure the boot in the longitudinal direction of the boot as well as against a lifting-off from the base parts, the edge of the boot-side plate part pointing to the tip of the boot may be embraced from the front and from above by a stationary claw or the like on one base part, while the edge of the plate part pointing to the heel of the ski boot is correspondingly embraced by the holding-down device. In this case, the holding down device, from its release position, may, when the ski boot is placed in the binding, be stepped down into the locking position by the heel area which projects over the boot-side plate part toward the rear.
In principle, a corresponding arrangement of the holding-down device is also possible on the tip of the boot.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.